Flight

Launch from the Baikonur Cosmodrome; landing
202 km east of Dzhezkazgan.

The double crew was the original prime
crew. This crew underwent their final medical checkups. A spot was found on
Valeri Kubasov's lung in the x-ray. The doctors say it is the
beginning of tuberculosis, and prohibit him from flying in space. After some
discussions the Soviets changed the complete crews.

The
Soyuz 11 launch proceeded without any difficulties.
The first orbital correction in the set of rendezvous maneuvers to head for
Salyut 1 was made on the fourth orbit.Following a
one day solo flight Soyuz 11 docked with the space station
Salyut 1 on
June 07, 1971. Aboard
Soyuz 11, the Igla automatic rendezvous and docking
system was switched on when the spacecraft was 7 km from
Salyut 1. There was no manual intervention in the
process; Georgi
Dobrovolsky simply made reports to the ground of the
rendezvous and docking system's progress. Docking itself took place out of
tracking range. There was considerable suspense in mission control during the
90-minute wait until reacquisition. Before leaving radio contact, telemetry
showed a signal that the docking mechanism had depressurized, which would have
prevented the cosmonauts from opening the hatch and entering the space station.
But when the station came back in view, it turned out that all went normally
and the crew had already entered the station. Viktor
Patsayev entered first, turned on the air regenerator, and
replaced two failed fans. The crew report said that the station atmosphere was
unpleasant, with a strong burned smell. It will take 20 hours for all of the
air in the station to cycle through the ECS scrubbers, so the crew is told to
spend the first night aboard their
Soyuz.It was the first space station flight in
space history.

When the crew awoke, the station air was all right, and
all eight fans and filters of the ECS are operating.
Soyuz 11 was powered down and put in storage mode. The
crew began the work program. But they had not yet put on their Penguin training
suits and were not yet following the exercise program. Clearly, they were not
taking the necessary steps to adapt to zero-G and preserve their health for
their return. They took control of the station for the first time, making an
orbital correction maneuver, and then orienting the station and its solar
panels fully toward the sun.A day later the cosmonauts put on their
training suits, and were urged to do regular physical training as required by
the program. There are enough ECS consumables, fuel, water, and food aboard for
the station to continue in manned operation until August 20,
1971.

Equipment aboard
Salyut 1 included a telescope, spectrometer,
electro-photometer, and television. The crew checked improved on-board
spacecraft systems in different conditions of flight and conducted
medico-biological research. The main instrument, a large solar telescope, was
inoperative because its cover failed to jettison.The crew performed
different scientific work in the areas of biology, astronomy and Earth
observation were part of the scientific work.

On June 16, 1971 the
cosmonauts reported a strong burning smell, and smoke in the station. The crew
evacuated the station and retreated to the
Soyuz lifeboat. Forty minutes later the situation
aboard the station is not comfortable. The crew had turned off the primary
oxygen regenerator and exchanged the filters of the oxygen supply and reserve
regenerator. The
Soyuz 11 crew later reported that the training suits
are very tiring. Georgi
Dobrovolsky reported all is now normal otherwise. He requests
permission to continue the flight. There was no more smoke or burning smell,
but the crew has been overloaded in the last six hours. They had done a lot of
work with no food or rest. The situation was so bad at one point that
preparations had been made for undocking the
Soyuz for an emergency return to
earth.

Meanwhile the electrical specialists in Moscow cannot localize
the electrical problem. All of the equipment aboard has been turned off and on,
and the burning simply does not occur again. Meanwhile there are concerns that
Soyuz 11 may be able to reach the desired mission
length.

The mission was cut short due of problems aboard the station
including the electrical fire. The planned highlight of the mission was to have
been the observation of an N-1 booster launch, but the launch was postponed.
The crew also found that using the exercise treadmill as they were required to
do twice a day caused the whole station to vibrate.

On June 26, 1971
the crew had completed all scientific and technical experiments aboard the
Salyut station. They will spend the last two to three
days concentrating on physical training, medical observations, and preparation
for landing. They will turn off all station equipment not required for
autonomous flight, prepare the
Soyuz for landing, and measure the water and
consumable reserves available for the next crew. The experiments have produced
many film cartridges, experiment samples, and so on that should be returned to
earth. However there is not enough space or mass reserves in the
Soyuz capsule for them all so they are only to return
those specifically listed by ground control.

On June 28, 1971 the
cosmonauts had to be extremely careful in putting
Salyut in storage mode. They went through the
checklist together with the ground to make sure no errors are made. The
Salyut station was much more comfortable than the
Soyuz, but the mission has revealed it needs many
improvements, including: a unit for ejecting liquids from the station; solar
panels, and scientific instruments, that can be automatically pointed at the
sun or their target and stabilized; an improved control section; better crew
rest provisions. Only with such improvements will it be possible to make
flights of two months or longer.

After the crew had left the station,
taken their seats in the capsule, and closed the hatch between the
Soyuz BO orbital module and SA re-entry capsule, the
strained voice of Vladislav
Volkov came from space: 'Hatch not hermetically sealed?
What's happening? What's going on?'. All this response to the fact that the
caution and warning panel 'Hatch open' light has not gone out. Aleksei
Yeliseyev calmly advised the crew, 'Don't panic. Open the
hatch, and move the wheel to the left to open. Close the hatch, and then move
the wheel to the right six turns with full force'. The crew did this several
times, but the light still won't go out. On a final attempt, with 6.5 turns of
the wheel, the light went out. The crew lowered the pressure in the BO to 160
mm, and the hatch proved to be air-tight.On the next orbit the crew
separated their
Soyuz from the
Salyut station. At 21:35 they reported normal
separation and that they 'can see how the station moves away from the
spacecraft'. They had enough propellant to stop the separation velocity, and
take photographs of the station from 10 to 15 m away. They then backed away to
30-40 m, and Viktor
Patsayev took another set of photographs documenting the
condition of the station.

The crew was told to report on HF and UHF
using all antennas and to call out parachute opening. They were ordered to wait
in the capsule for the recovery crews, not to open the hatch themselves under
any circumstances. It should take no more than 20 to 30 minutes until the
recovery team can open the hatch from the outside. They are under no
circumstances to try to get out of the capsule without the assistance of the
doctors. Georgi
Dobrovolsky confirmed: "All received, landing sequence
proceeding excellent, all OK, crew is excellent".

Telemetry showed the
Soyuz braking engine began firing at 01:35:24 and made
a nominal 187 second retrofire burn. Ground control waited for verbal
confirmation, but there were no voice communications received from the capsule.
At 01:47:28 the crew should have reported successful BO and PAO module
separations from the capsule, but still nothing heard.

A pressure
equalization valve was jerked loose at the jettison of the
Soyuz Orbital Module. The valve was not supposed to
open until an altitude of 4 km was reached. The medical experts had
determined that the cosmonauts died from depressurization of the
spacecraft. The crew had hemorrhages in their brains, blood in their lungs,
and nitrogen in their blood. The flight recorder showed that four seconds after
the depressurization began Georgi
Dobrovolsky's breathing rate went to 48/minute (normally
16/minute), asphyxiation began, and 20 to 30 seconds later he was dead.The
three-man crew did not have space suits. The
Soyuz was thereafter redesigned to accommodate only
two crew members, but in spacesuits. When the hatch was opened it was found
that the crew had perished due to a loss of cabin atmosphere. As a result of
this disaster pressure suits were worn during launch, docking maneuvers and
reentry in the following missions.

It quickly became apparent that they
had asphyxiated. The fault was traced to a breathing ventilation valve, located
between the orbital module and the descent module, that had been jolted open as
the descent module separated from the service module, 723 seconds after
retrofire. The two were held together by explosive bolts designed to fire
sequentially; in fact, they fired simultaneously. The force of this caused the
internal mechanism of the pressure equalization valve to loosen a seal that was
usually discarded later and normally allowed automatic adjustment of the cabin
pressure. The valve opened at an altitude of 168 kilometers (104 mi), and the
gradual loss of pressure was fatal within seconds. The valve was located
beneath the seats and was impossible to find and block before the air was lost.
Flight recorder data from the single cosmonaut outfitted with biomedical
sensors showed cardiac arrest occurred within 40 seconds of pressure loss. By
935 seconds after the retrofire, the cabin pressure was zero, and remained
there until the capsule entered the Earth's atmosphere.